eprintid: 10043086 rev_number: 25 eprint_status: archive userid: 608 dir: disk0/10/04/30/86 datestamp: 2018-02-13 10:38:48 lastmod: 2022-01-11 00:09:40 status_changed: 2018-02-13 10:38:48 type: article metadata_visibility: show creators_name: Koulaouzidis, A creators_name: Iakovidis, DK creators_name: Yung, DE creators_name: Mazomenos, E creators_name: Bianchi, F creators_name: Karagyris, A creators_name: Dimas, G creators_name: Stoyanov, D creators_name: Thorlacius, H creators_name: Toth, E creators_name: Ciuti, G title: Novel experimental and software methods for image reconstruction and localization in capsule endoscopy ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F48 divisions: F42 note: This article is published under a Creative Commons licence CC BY-NC-ND 4.0. abstract: BACKGROUND AND STUDY AIMS: Capsule endoscopy (CE) is invaluable for minimally invasive endoscopy of the gastrointestinal tract; however, several technological limitations remain including lack of reliable lesion localization. We present an approach to 3D reconstruction and localization using visual information from 2D CE images. PATIENTS AND METHODS: Colored thumbtacks were secured in rows to the internal wall of a LifeLike bowel model. A PillCam SB3 was calibrated and navigated linearly through the lumen by a high-precision robotic arm. The motion estimation algorithm used data (light falling on the object, fraction of reflected light and surface geometry) from 2D CE images in the video sequence to achieve 3D reconstruction of the bowel model at various frames. The ORB-SLAM technique was used for 3D reconstruction and CE localization within the reconstructed model. This algorithm compared pairs of points between images for reconstruction and localization. RESULTS: As the capsule moved through the model bowel 42 to 66 video frames were obtained per pass. Mean absolute error in the estimated distance travelled by the CE was 4.1 ± 3.9 cm. Our algorithm was able to reconstruct the cylindrical shape of the model bowel with details of the attached thumbtacks. ORB-SLAM successfully reconstructed the bowel wall from simultaneous frames of the CE video. The "track" in the reconstruction corresponded well with the linear forwards-backwards movement of the capsule through the model lumen. CONCLUSION: The reconstruction methods, detailed above, were able to achieve good quality reconstruction of the bowel model and localization of the capsule trajectory using information from the CE video and images alone. date: 2018-02 date_type: published official_url: http://dx.doi.org/10.1055/s-0043-121882 oa_status: green full_text_type: pub pmcid: PMC5794451 language: eng primo: open primo_central: open_green article_type_text: Journal Article verified: verified_manual elements_id: 1533291 doi: 10.1055/s-0043-121882 lyricists_name: Mazomenos, Evangelos lyricists_name: Stoyanov, Danail lyricists_id: EMAZO45 lyricists_id: DSTOY26 actors_name: Stoyanov, Danail actors_id: DSTOY26 actors_role: owner full_text_status: public publication: Endoscopy International Open volume: 6 number: 2 pagerange: E205-E210 event_location: Germany issn: 2364-3722 citation: Koulaouzidis, A; Iakovidis, DK; Yung, DE; Mazomenos, E; Bianchi, F; Karagyris, A; Dimas, G; ... Ciuti, G; + view all <#> Koulaouzidis, A; Iakovidis, DK; Yung, DE; Mazomenos, E; Bianchi, F; Karagyris, A; Dimas, G; Stoyanov, D; Thorlacius, H; Toth, E; Ciuti, G; - view fewer <#> (2018) Novel experimental and software methods for image reconstruction and localization in capsule endoscopy. Endoscopy International Open , 6 (2) E205-E210. 10.1055/s-0043-121882 <https://doi.org/10.1055/s-0043-121882>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10043086/1/Novel%20experimental%20and%20software%20methods%20for%20image%20reconstruction%20and%20localization%20in%20capsule%20endoscopy.pdf